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arXiv · 2512.23560

Spectral reconstruction based on dimensional reduction in high-temperature gauge theories

P. V. Buividovich·B. Hind
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Abstract

We propose a numerical spectral reconstruction workflow for high-temperature gauge theories that incorporates elements of semi-classical real-time evolution directly into standard lattice QCD simulations via high-temperature dimensional reduction, thus counteracting the deterioration of Euclidean-time correlators at high temperatures. With a moderate numerical cost, our method allows to estimate spectral functions with parametrically better frequency resolution as compared with spectral reconstruction methods based on Euclidean-time correlators alone. The method is tested on a simple (1+1)-dimensional Abelian gauge theory with fermions, where our method precisely reproduces the full quantum spectral functions calculated using exact numerical diagonalization in the high-temperature, weak-coupling regime. We also demonstrate the feasibility of our approach by applying it to light-quark meson correlators in lattice QCD deep in the deconfinement regime.

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P. V. Buividovich, B. Hind. 2025-12-29. Spectral reconstruction based on dimensional reduction in high-temperature gauge theories. https://arxiv.org/abs/2512.23560

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